Many people suffer from an inability to control urinary function, i.e., urinary incontinence. Different muscles, nerves, organs and conduits within the urinary tract cooperate to collect, store and release urine. A variety of disorders may compromise urinary tract performance and contribute to incontinence. Many of the disorders may be associated with aging, injury or illness. For example, aging can often result in weakened sphincter muscles, which cause incontinence, or weakened bladder muscles, which prevent complete emptying. Some patients also may suffer from nerve disorders that prevent proper triggering and operation of the bladder or sphincter muscles.
One symptom of urinary incontinence is nocturia, which is characterized by the need to urinate while a patient is sleeping (i.e., during a sleep event), thereby possibly interrupting a sleep state of the patient. Nocturia may also be a symptom of other problems, such as interstitial cystitis, diabetes, benign prostatic hyperplascia or prostate cancer.
Fecal incontinence is the inability to control bowel function. Fecal incontinence may be attributable to many physiological conditions, such as muscle damage to the muscles of the rectum (e.g., the anal internal or external sphincters), nerve damage, loss of storage capacity within the rectum, and pelvic floor dysfunction. One symptom of fecal incontinence is similar to nocturia in that a patient experiences a fecal voiding urge during a sleep event.
Electrical stimulation of nerves in the pelvic floor may provide an effective therapy for a variety of disorders, including urinary incontinence and fecal incontinence. For example, an implantable electrical stimulator may be provided. The electrical stimulator may be a neurostimulator that delivers electrical stimulation to the sacral nerve to induce sphincter constriction and thereby close or maintain closure of the urethra at the bladder neck. In addition, electrical stimulation of the bladder wall may enhance pelvic floor muscle tone and assist fluid retention in the bladder or voiding fluid from the bladder.